Minor fixes to 'hacking.html'.
Minor fixes to 'hacking.html'.

Suggested by: Osku Salerma <osku@iki.fi>

* www/hacking.html
  (participating): Remove an extraneous nonsense word.
  (release-numbering): Update the details of version numbering of
    development builds to match the current reality.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion